Adapter assembly for interconnecting electromechanical surgical devices and surgical loading units, and surgical systems thereof

ABSTRACT

The present disclosure relates to adapter assemblies for use with and to electrically and mechanically interconnect electromechanical surgical devices and surgical loading units, and to surgical systems including hand held electromechanical surgical devices and adapter assemblies for connecting surgical loading units to the hand held electromechanical surgical devices.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. Provisional Patent Application No. 62/017,610, filed Jun. 26, 2014, the entire disclosure of which is incorporated by reference herein.

BACKGROUND

1. Technical Field

The present disclosure relates to adapter assemblies for use in surgical systems. More specifically, the present disclosure relates to adapter assemblies for use with and to electrically and mechanically interconnect electromechanical surgical devices and surgical loading units, and to surgical systems including hand held electromechanical surgical devices and adapter assemblies for connecting surgical loading units to the hand held electromechanical surgical devices.

2. Background of Related Art

A number of surgical device manufacturers have developed product lines with proprietary drive systems for operating and/or manipulating electromechanical surgical devices. In many instances the electromechanical surgical devices include a handle assembly, which is reusable, and disposable loading units and/or single use loading units or the like that are selectively connected to the handle assembly prior to use and then disconnected from the handle assembly following use in order to be disposed of or in some instances sterilized for re-use.

In certain instances, an adapter assembly is used to interconnect an electromechanical surgical device with any one of a number of surgical loading units to establish a mechanical and/or electrical connection therebetween. Due to the complexity of the adapter assembly and the electromechanical surgical device, it is important to ensure that all electrical and mechanical connections therebetween can be easily, reliably and repeatedly accomplished.

Accordingly, a need exists for an adapter assembly that provides a robust way of electromechanically interconnecting with the surgical device.

SUMMARY

The present disclosure relates to adapter assemblies for use with and to electrically and mechanically interconnect electromechanical surgical devices and surgical loading units, and to surgical systems including hand held electromechanical surgical devices and adapter assemblies for connecting surgical loading units to the hand held electromechanical surgical devices.

According to an aspect of the present disclosure, an adapter assembly for selectively interconnecting a surgical loading unit that is configured to perform a function and a surgical device that is configured to actuate the loading unit, is provided. The loading unit may include at least one axially translatable drive member, and the surgical device may include at least one rotatable drive shaft. The adapter assembly includes a housing configured and adapted for connection with the surgical device and to be in operative communication with each rotatable drive shaft of the surgical device; an outer tube having a proximal end supported by the housing and a distal end configured and adapted for connection with the loading unit, wherein the distal end of the outer tube is in operative communication with each of the axially translatable drive member of the loading unit; the force/rotation transmitting/converting assembly for interconnecting a respective one drive shaft of the surgical device and a respective one axially translatable drive member of the loading unit; and an electrical assembly supported within at least one of the housing and the outer tube. The electrical assembly includes a proximal electrical assembly and a distal electrical assembly. The proximal electrical assembly is configured to electrically communicate with the surgical device. The proximal electrical assembly is rotatably fixed with respect to the surgical device, and the proximal electrical assembly includes a plurality of electrical contact rings disposed around a slip ring. The distal electrical assembly is disposed in electrical communication with the loading unit, and is rotatable with respect to the proximal electrical assembly. The distal electrical assembly includes a plurality of electrical contacts disposed in mechanical cooperation with a contact housing. Each electrical contact is configured to contact and maintain an electrical connection with one of the plurality of electrical contact rings of the proximal electrical assembly during rotation of the distal electrical assembly with respect to the proximal electrical assembly.

In disclosed embodiments, each electrical contact of the distal electrical assembly is curved along at least a majority of its length. It is further disclosed that each electrical contact of the distal electrical assembly includes a continuous curve in a first direction, and the plurality of electrical contact rings of the proximal electrical assembly are curved in a second direction. Here, the first and second directions are opposite from each other.

It is further disclosed that each electrical contact of the distal electrical assembly includes a leg and a foot, with the leg extending from the contact housing, and the foot extending at an angle from the leg. A portion of the foot configured to contact one of the plurality of electrical contact rings. The angle is between about 100° and about 160°.

The present disclosure also includes embodiments where each electrical contact of the distal electrical assembly includes a leg and two feet. The leg extends from the contact housing, each foot extends at an angle from the leg in opposite directions, and a portion of each foot is configured to contact one of the plurality of electrical contact rings. The angle is between about 100° and about 160°.

In disclosed embodiments, each electrical contact of the distal electrical assembly includes a leg, an ankle and an arcuate foot. The leg extends from the contact housing, the ankle extends at a first angle from the leg, and the arcuate foot extends at a second angle from the ankle. At least two portions of the arcuate foot are configured to contact one of the plurality of electrical contact rings. The first angle is between about 150° and about 175°, and the second angle is between about 10° and about 60°. Here, it is further disclosed that the arcuate foot includes a radius of curvature that is less than or equal to a radius of curvature of the plurality of electrical contact rings.

It is further disclosed that each electrical contact of the distal electrical assembly includes a leg, two feet extending from the leg in an opposite directions, and a flexible contact extending between the two feet. At least a portion of the flexible contact is configured to contact one of the plurality of electrical contact rings. Here, it is disclosed that the flexible contact is movable with respect to at least one foot.

In disclosed embodiments, each electrical contact of the distal electrical assembly includes a leg and a ring. The leg extends from the contact housing, and the ring extends from the leg. The ring is configured to contact one of the plurality of electrical contact rings in an arc of greater than 180°. Here, it is disclosed that the ring forms between about 180° and about 360° of a circle.

The present disclosure also includes embodiments where the contact housing includes a proximal leg configured to engage a proximal-most edge of the slip ring, and a distal leg configured to engage a distal-most edge of the slip ring. Here, it is disclosed that each leg of the contact housing includes a stepped portion. At least part of the stepped portion is configured to engage a radially-outermost portion of the slip ring.

In disclosed embodiments, the distal electrical assembly further includes a guide configured to help maintain a position of the contact housing with respect to the slip ring. Here, it is disclosed that the guide is configured to help maintain a longitudinal position and a radial position of the contact housing with respect to the slip ring. It is further disclosed that the guide includes an opening for receiving at least a portion of the contact housing therein, and that the guide includes a flexible member for extending between a pair of projections of the contact housing and for abutting a radially-outer surface of at least one of the projections of the contact housing. Additionally, embodiments disclose that the guide includes a first post extending adjacent a first portion of the opening for extending between a pair of projections of the contact housing, and that the guide includes a second post extending adjacent a second portion of the opening for engaging a portion of the contact housing. The first portion and the second portion are on opposite sides of the opening. The disclosure also includes that the contact housing includes at least one projection, and that the guide includes at least one flexible tab for engaging a radially-outer surface of the at least one projection of the contact housing. Further, it is disclosed that the contact housing includes at least two projections, and that the guide includes at least two flexible tabs. Each flexible tab is configured to engage a radially-outer surface of one of the at least two projections of the contact housing.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure are described herein with reference to the accompanying drawings, wherein:

FIG. 1A is a perspective view of an adapter assembly, in accordance with an embodiment of the present disclosure, interconnected between an exemplary electromechanical surgical device and an end effector assembly;

FIG. 1B is a perspective view illustrating an attachment of a proximal end of the adapter assembly to a distal end of the electromechanical surgical device;

FIG. 2A is a front, perspective view of the adapter assembly of the present disclosure;

FIG. 2B is a rear, perspective view of the adapter assembly of FIG. 2A;

FIG. 3 is a top plan view of the adapter assembly of FIGS. 2A and 2B;

FIG. 4 is a side, elevational view of the adapter assembly of FIGS. 2A and 2B;

FIG. 5 is a rear, perspective view of the adapter assembly of FIGS. 2A and 2B, with some parts thereof separated;

FIG. 6 is a rear, perspective view of the adapter assembly of FIGS. 2A and 2B, with most parts thereof separated;

FIG. 7 is a perspective view of an articulation assembly of the adapter assembly of FIGS. 2A and 2B;

FIG. 8 is an enlarged, perspective view, with parts separated, of the articulation assembly of FIG. 7;

FIG. 9 is a perspective view of the articulation assembly of FIG. 7, shown in a first orientation;

FIG. 10 is a perspective view of the articulation assembly of FIG. 7, shown in a second orientation;

FIG. 11 is a cross-sectional view as taken along section line 11-11 of FIG. 9;

FIG. 12A is a perspective view of an electrical assembly of the adapter assembly of FIGS. 2A and 2B;

FIG. 12B is a perspective view of the electrical assembly of FIG. 12A showing a connector housing separated from a circuit board;

FIG. 12C is a perspective view of the connector housing of FIG. 12B;

FIG. 12D is a perspective view of an electrical contact pin of the connector housing of FIGS. 12B-12C;

FIG. 13 is a perspective view of the electrical assembly of FIG. 12 shown connected to the core housing of the adapter assembly of FIGS. 2A and 2B;

FIG. 14 is a cross-sectional view as taken along section line 14-14 of FIG. 13;

FIG. 15 is a perspective view of a slip ring cannula or sleeve of the adapter assembly of FIGS. 2A and 2B;

FIG. 16 is an enlarged view of the indicated area of detail of FIG. 2B, illustrating an inner housing assembly of the adapter assembly of FIGS. 2A and 2B;

FIG. 17 is a rear, perspective view of the inner housing assembly of FIG. 16 with an outer knob housing half-section and a proximal cap removed therefrom;

FIG. 18 is a rear, perspective view of the inner housing assembly of FIG. 16 with the outer knob housing, the proximal cap and a bushing plate removed therefrom;

FIG. 19 is a rear, perspective view of the inner housing assembly of FIG. 16 with the outer knob housing, the proximal cap, the bushing plate and an inner housing removed therefrom;

FIG. 20 is a rear, perspective view of the an alternative embodiment of inner housing assembly similar to that shown in FIG. 16 with the outer knob housing and the proximal inner housing removed therefrom;

FIG. 21 is a rear, perspective view of the inner housing assembly of FIG. 20 with the outer knob housing, the proximal inner housing and the articulation assembly removed therefrom;

FIG. 22 is a front, perspective view of the inner housing assembly of FIG. 20 with the outer knob housing, the proximal inner housing and the articulation assembly removed therefrom;

FIG. 23 is a front, perspective view of the inner housing assembly of FIG. 20 with the outer knob housing and the proximal inner housing removed therefrom;

FIG. 24 is a cross-sectional view as taken along section line 24-24 of FIG. 2B;

FIG. 25 is an enlarged view of the indicated area of detail of FIG. 24;

FIG. 26 is an enlarged view of the indicated area of detail of FIG. 24, illustrating a lock button being actuated in a proximal direction;

FIG. 27 is a cross-sectional view as taken along section line 27-27 of FIG. 2B;

FIG. 28 is a cross-sectional view as taken along section line 27-27 of FIG. 2B, illustrating actuation of the articulation assembly in a distal direction;

FIG. 29 is a cross-sectional view as taken along section line 29-29 of FIG. 28;

FIG. 30 is a cross-sectional view as taken along section line 30-30 of FIG. 28;

FIG. 31 is a cross-sectional view as taken along section line 31-31 of FIG. 28;

FIG. 32 is a rear, perspective view of a proximal inner housing hub according to the present disclosure;

FIG. 33 is a front, perspective view of the proximal inner housing hub of FIG. 32;

FIG. 34 is a front, perspective view of the proximal inner housing hub of FIGS. 32 and 33 illustrating a first and a second force/rotation transmitting/converting assembly and a reinforcing assembly associated therewith;

FIG. 35 is a front, perspective view of a plate bushing of the proximal inner housing assembly of the present disclosure;

FIG. 36 is a rear, perspective view of the plate bushing of FIG. 35;

FIG. 37 is a rear, perspective view of the proximal inner housing assembly illustrating the plate bushing of FIGS. 35 and 36 attached thereto;

FIG. 38 is a rear, perspective view of the proximal inner housing assembly of FIG. 37 with connector sleeves removed therefrom;

FIG. 39 is a rear, perspective view of the proximal inner housing assembly of FIG. 37 with connector sleeves removed therefrom and the plate bushing shown in phantom;

FIG. 40 is a rear, perspective view of the proximal inner housing assembly of FIG. 37 with connector sleeves removed therefrom;

FIG. 41 is a rear, perspective of the inner housing assembly of FIG. 37 illustrating a support plate, according to another embodiment of the present disclosure, coupled thereto;

FIG. 42 is a rear, perspective of the inner housing assembly of FIG. 41 with the support plate removed therefrom;

FIG. 43 is a front, perspective view of an inner housing assembly according to another embodiment of the present disclosure with the outer knob housing, the proximal inner housing removed therefrom;

FIG. 44 is a rear, perspective view of the inner housing assembly of FIG. 43 with the outer knob housing, the proximal inner housing and the articulation assembly removed therefrom;

FIG. 45 is a perspective view of a bracket assembly of the inner housing assembly of FIGS. 43 and 44;

FIG. 46 is a perspective view of a reinforcing sleeve for use with the inner housing assembly of FIGS. 43 and 44;

FIG. 47 is a perspective view of the inner housing assembly of FIGS. 43 and 44, illustrating the reinforcing sleeve of FIG. 46 supported thereon;

FIG. 48 is a perspective view, with parts separated, of an exemplary loading unit for use with the surgical device and the adapter of the present disclosure;

FIG. 49 is a perspective view of an adapter assembly in accordance with the present disclosure with several features shown in phantom;

FIG. 50 is a perspective view of proximal and distal electrical assemblies of the adapter assembly of FIG. 49;

FIG. 51 is an enlarged view of the area of detail indicated in FIG. 50 showing engagement between the proximal and distal electrical assemblies of FIG. 50;

FIG. 52 is a perspective view of the distal electrical assembly of FIGS. 49 and 50;

FIG. 53 is an enlarged view of the area of detail indicated in FIG. 52;

FIG. 54 is a perspective view illustrating the engagement between portions of the proximal and distal electrical assemblies of FIGS. 49-53;

FIG. 55 is a perspective view of the portion of the distal electrical assembly shown in FIG. 54;

FIGS. 56A-60A are side views of the proximal electrical assembly and various embodiments of the portion of the distal electrical assembly that engages the proximal electrical assembly;

FIGS. 56B-60B are perspective views of FIGS. 56A-60A, respectively;

FIG. 61 is a perspective view of a guide in accordance with an embodiment of the present disclosure;

FIG. 62 is a perspective view of a portion of the surgical device of the present disclosure including the guide of FIG. 61;

FIG. 63 is a perspective view of a guide in accordance with an embodiment of the present disclosure;

FIG. 64 is a perspective view of a portion of the surgical device of the present disclosure including the guide of FIG. 63;

FIG. 65 is a perspective view of a portion of a guide in accordance with an embodiment of the present disclosure;

FIG. 66 is a perspective view of a portion of the surgical device of the present disclosure including the guide of FIG. 65;

FIG. 67 is a perspective view of a portion of a guide in accordance with another embodiment of the present disclosure;

FIG. 68 is a perspective view of a portion of the surgical device of the present disclosure including the guide of FIG. 67;

FIG. 69 is a perspective view of a housing in accordance with an embodiment of the present disclosure;

FIG. 70 is a perspective view of a portion of the surgical device of the present disclosure including the housing of FIG. 69 engaged with the guide of FIG. 60;

FIG. 71 is a perspective view of a guide in accordance with yet another embodiment of the present disclosure;

FIG. 72 is a perspective view of a portion of the surgical device of the present disclosure including the guide of FIG. 71;

FIG. 73 is a perspective view of a portion of a guide in accordance with still another embodiment of the present disclosure;

FIG. 74 is a perspective view of a portion of the surgical device of the present disclosure including the guide of FIG. 73;

FIG. 75 is a perspective view of a spacer of the surgical device in accordance with an embodiment of the present disclosure;

FIGS. 76A and 76B are perspective views of a slip ring contact holder for use with the spacer of FIG. 75 in accordance with embodiments of the present disclosure;

FIGS. 77 and 78 are perspective views of the slip ring contact holder of FIGS. 76A and 76B engaged with the spacer of FIG. 75;

FIG. 79 is a perspective view of a disclosed embodiment of a slip ring contact holder engaged with the spacer of FIG. 75;

FIG. 80 is a perspective view of a slip ring cannula in accordance with an embodiment of the present disclosure;

FIG. 81 is a perspective view of the slip ring cannula of FIG. 80 shown over an outer tube of the adapter assembly;

FIGS. 82 and 83 are perspective views of the slip ring cannula of FIGS. 80 and 81 shown over the outer tube of the adapter assembly and engaged with a portion of the inner housing assembly;

FIG. 84 is a perspective view of a portion of the adapter assembly including an alternate embodiment of a slip ring contact holder in accordance with the present disclosure; and

FIG. 85 is a cross-sectional view of the adapter assembly including the slip ring contact holder of FIG. 84.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed surgical devices, adapter assemblies, and loading unit detection assemblies for surgical devices and/or handle assemblies are described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein the term “distal” refers to that portion of the adapter assembly or surgical device, or component thereof, farther from the user, while the term “proximal” refers to that portion of the adapter assembly or surgical device, or component thereof, closer to the user.

A surgical device, in accordance with an embodiment of the present disclosure, is generally designated as 100, and is in the form of a powered hand held electromechanical instrument configured for selective attachment thereto of a plurality of different end effectors that are each configured for actuation and manipulation by the powered hand held electromechanical surgical instrument.

As illustrated in FIG. 1A, surgical device 100 is configured for selective connection with an adapter assembly 200, and, in turn, adapter assembly 200 is configured for selective connection with a loading unit 300 (e.g., an end effector, or multiple- or single-use loading unit; see FIG. 48). Surgical device 100 and adapter assembly 200, together, may comprise an electromechanical surgical system that is configured and adapted to selectively connect with a loading unit 300 and to actuate loading unit 300.

As illustrated in FIGS. 1A and 1B, surgical device 100 includes a handle housing 102 including a circuit board (not shown), and a drive mechanism (not shown) is situated therein. The circuit board is configured to control the various operations of surgical device 100. Handle housing 102 defines a cavity therein (not shown) for selective removable receipt of a rechargeable battery (not shown) therein. The battery is configured to supply power to any of the electrical components of surgical device 100.

Handle housing 102 includes an upper housing portion 102 a which houses various components of surgical device 100, and a lower hand grip portion 102 b extending from upper housing portion 102 a. Lower hand grip portion 102 b may be disposed distally of a proximal-most end of upper housing portion 102 a. The location of lower housing portion 102 b relative to upper housing portion 102 a is selected to balance a weight of a surgical device 100 that it is connected to or supporting adapter assembly 200 and/or end effector 300.

Handle housing 102 provides a housing in which the drive mechanism is situated. The drive mechanism is configured to drive shafts and/or gear components in order to perform the various operations of surgical device 100. In particular, the drive mechanism is configured to drive shafts and/or gear components in order to selectively move a tool assembly 304 of loading unit 300 (see FIGS. 1A and 48) relative to a proximal body portion 302 of loading unit 300, to rotate loading unit 300 about a longitudinal axis “X” (see FIG. 1A) relative to handle housing 102, to move/approximate an anvil assembly 306 and/or a cartridge assembly 308 of loading unit 300 relative to one another, and/or to fire a stapling and cutting cartridge within cartridge assembly 308 of loading unit 300.

As illustrated in FIG. 1B, handle housing 102 defines a connecting portion 108 configured to accept a corresponding drive coupling assembly 210 of adapter assembly 200. Specifically, connecting portion 108 of surgical device 100 has a recess 108 a that receives a proximal cap 210 a (FIGS. 5 and 6) of drive coupling assembly 210 of adapter assembly 200 when adapter assembly 200 is mated to surgical device 100. Connecting portion 108 houses three rotatable drive connectors 118, 120, 122 which are arranged in a common plane or line with one another.

When adapter assembly 200 is mated to surgical device 100, each of rotatable drive connectors 118, 120, 122 of surgical device 100 couples with a corresponding rotatable connector sleeve 218, 220, 222 of adapter assembly 200 (see FIG. 1B). In this regard, the interface between corresponding first drive connector 118 and first connector sleeve 218, the interface between corresponding second drive connector 120 and second connector sleeve 220, and the interface between corresponding third drive connector 122 and third connector sleeve 222 are keyed such that rotation of each of drive connectors 118, 120, 122 of surgical device 100 causes a corresponding rotation of the corresponding connector sleeve 218, 220, 222 of adapter assembly 200.

The mating of drive connectors 118, 120, 122 of surgical device 100 with connector sleeves 218, 220, 222 of adapter assembly 200 allows rotational forces to be independently transmitted via each of the three respective connector interfaces. The drive connectors 118, 120, 122 of surgical device 100 are configured to be independently rotated by the drive mechanism of surgical device 100. In this regard, a function selection module (not shown) of the drive mechanism selects which drive connector or connectors 118, 120, 122 of surgical device 100 is to be driven by the motor of surgical device 100.

Since each of drive connectors 118, 120, 122 of surgical device 100 has a keyed and/or substantially non-rotatable interface with respective connector sleeves 218, 220, 222 of adapter assembly 200, when adapter assembly 200 is coupled to surgical device 100, rotational force(s) are selectively transferred from drive connectors of surgical device 100 to adapter assembly 200.

The selective rotation of drive connector(s) 118, 120 and/or 122 of surgical device 100 allows surgical device 100 to selectively actuate different functions of loading unit 300. For example, selective and independent rotation of first drive connector 118 of surgical device 100 corresponds to the selective and independent opening and closing of tool assembly 304 of loading unit 300, and driving of a stapling/cutting component of tool assembly 304 of loading unit 300. As an additional example, the selective and independent rotation of second drive connector 120 of surgical device 100 corresponds to the selective and independent articulation of tool assembly 304 of loading unit 300 transverse to longitudinal axis “X” (see FIG. 1A). Additionally, for instance, the selective and independent rotation of third drive connector 122 of surgical device 100 corresponds to the selective and independent rotation of loading unit 300 about longitudinal axis “X” (see FIG. 1A) relative to handle housing 102 of surgical device 100.

As illustrated in FIG. 1A, handle housing 102 supports a plurality of finger-actuated control buttons, rocker devices and the like for activating various functions of surgical device 100.

Reference may be made to International Application No. PCT/US2008/077249, filed Sep. 22, 2008 (Inter. Pub. No. WO 2009/039506) and U.S. patent application Ser. No. 12/622,827, filed on Nov. 20, 2009, the entire content of each of which being incorporated herein by reference, for a detailed description of various internal components of and operation of exemplary electromechanical, hand-held, powered surgical instrument 100.

With particular reference to FIGS. 1B-2B, adapter assembly 200 includes an outer knob housing 202 and an outer tube 206 extending from a distal end of knob housing 202. Knob housing 202 and outer tube 206 are configured and dimensioned to house the components of adapter assembly 200. Outer tube 206 is dimensioned for endoscopic insertion, in particular, outer tube 206 is passable through a typical trocar port, cannula or the like. Knob housing 202 is dimensioned to not enter the trocar port, cannula of the like. Knob housing 202 is configured and adapted to connect to connecting portion 108 of handle housing 102 of surgical device 100.

Adapter assembly 200 is configured to convert a rotation of either of drive connectors 118, 120 and 122 of surgical device 100 into axial translation useful for operating a drive assembly 360 and an articulation link 366 of loading unit 300, as illustrated in FIG. 48 and as will be described in greater detail below. As illustrated in FIGS. 5, 6, 13, 14, 17, 18, 20, 25-34 and 37-40, adapter assembly 200 includes a proximal inner housing assembly 204 rotatably supporting a first rotatable proximal drive shaft 212, a second rotatable proximal drive shaft 214, and a third rotatable proximal drive shaft 216 therein. Each proximal drive shaft 212, 214, 216 functions as a rotation receiving member to receive rotational forces from respective drive shafts of surgical device 100, as described in greater detail below.

As described briefly above, inner housing assembly 210 of shaft assembly 200 is also configured to rotatably support first, second and third connector sleeves 218, 220 and 222, respectively, arranged in a common plane or line with one another. Each of connector sleeves 218, 220, 222 is configured to mate with respective first, second and third drive connectors 118, 120, 122 of surgical device 100, as described above. Each of connector sleeves 218, 220, 222 is further configured to mate with a proximal end of respective first, second and third proximal drive shafts 212, 214, 216.

Inner housing assembly 210 also includes, as illustrated in FIGS. 6, 17, 27 and 28, a first, a second and a third biasing member 224, 226 and 228 disposed distally of respective first, second and third connector sleeves 218, 220, 222. Each of biasing members 224, 226 and 228 is disposed about respective first, second and third rotatable proximal drive shaft 212, 214 and 216. Biasing members 224, 226 and 228 act on respective connector sleeves 218, 220 and 222 to help maintain connector sleeves 218, 220 and 222 engaged with the distal end of respective drive rotatable drive connectors 118, 120, 122 of surgical device 100 when adapter assembly 200 is connected to surgical device 100.

In particular, first, second and third biasing members 224, 226 and 228 function to bias respective connector sleeves 218, 220 and 222 in a proximal direction. In this manner, during assembly of adapter assembly 200 to surgical device 100, if first, second and or third connector sleeves 218, 220 and/or 222 is/are misaligned with the drive connectors 118, 120, 122 of surgical device 100, first, second and/or third biasing member(s) 224, 226 and/or 228 are compressed. Thus, when surgical device 100 is operated, drive connectors 118, 120, 122 of surgical device 100 will rotate and first, second and/or third biasing member(s) 224, 226 and/or 228 will cause respective first, second and/or third connector sleeve(s) 218, 220 and/or 222 to slide back proximally, effectively coupling drive connectors 118, 120, 122 of surgical device 100 to first, second and/or third proximal drive shaft(s) 212, 214 and 216 of inner housing assembly 210.

Adapter assembly 200 includes a plurality of force/rotation transmitting/converting assemblies, each disposed within inner housing assembly 204 and outer tube 206. Each force/rotation transmitting/converting assembly is configured and adapted to transmit/convert a speed/force of rotation (e.g., increase or decrease) of first, second and third rotatable drive connectors 118, 120 and 122 of surgical instrument 100 before transmission of such rotational speed/force to loading unit 300.

Specifically, as illustrated in FIG. 6, adapter assembly 200 includes a first, a second and a third force/rotation transmitting/converting assembly 240, 250, 260, respectively, disposed within inner housing 208 and outer tube 206. Each force/rotation transmitting/converting assembly 240, 250, 260 is configured and adapted to transmit or convert a rotation of a first, second and third drive connector 118, 120, 122 of surgical device 100 into axial translation of articulation bar 258 of adapter assembly 200, to effectuate articulation of loading unit 300; a rotation of a ring gear 266 of adapter assembly 200, to effectuate rotation of adapter assembly 200; or axial translation of a distal drive member 248 of adapter assembly 200 to effectuate closing, opening and firing of loading unit 300.

As shown in FIGS. 5, 6 and 24-31, first force/rotation transmitting/converting assembly 240 includes first rotatable proximal drive shaft 212, which, as described above, is rotatably supported within inner housing assembly 204. First rotatable proximal drive shaft 212 includes a non-circular or shaped proximal end portion configured for connection with first connector 218 which is connected to respective first connector 118 of surgical device 100. First rotatable proximal drive shaft 212 includes a distal end portion 212 b having a threaded outer profile or surface.

First force/rotation transmitting/converting assembly 240 further includes a drive coupling nut 244 rotatably coupled to threaded distal end portion 212 b of first rotatable proximal drive shaft 212, and which is slidably disposed within outer tube 206. Drive coupling nut 244 is slidably keyed within proximal core tube portion of outer tube 206 so as to be prevented from rotation as first rotatable proximal drive shaft 212 is rotated. In this manner, as first rotatable proximal drive shaft 212 is rotated, drive coupling nut 244 is translated along threaded distal end portion 212 b of first rotatable proximal drive shaft 212 and, in turn, through and/or along outer tube 206.

First force/rotation transmitting/converting assembly 240 further includes a distal drive member 248 that is mechanically engaged with drive coupling nut 244, such that axial movement of drive coupling nut 244 results in a corresponding amount of axial movement of distal drive member 248. The distal end portion of distal drive member 248 supports a connection member 247 configured and dimensioned for selective engagement with a drive member 374 of drive assembly 360 of loading unit 300 (FIG. 48). Drive coupling nut 244 and/or distal drive member 248 function as a force transmitting member to components of loading unit 300, as described in greater detail below.

In operation, as first rotatable proximal drive shaft 212 is rotated, due to a rotation of first connector sleeve 218, as a result of the rotation of the first respective drive connector 118 of surgical device 100, drive coupling nut 244 is caused to be translated axially along first distal drive shaft 242. As drive coupling nut 244 is caused to be translated axially along first distal drive shaft 242, distal drive member 248 is caused to be translated axially relative to outer tube 206. As distal drive member 248 is translated axially, with connection member 247 connected thereto and engaged with drive member 374 of drive assembly 360 of loading unit 300 (FIG. 48), distal drive member 248 causes concomitant axial translation of drive member 374 of loading unit 300 to effectuate a closure of tool assembly 304 and a firing of tool assembly 304 of loading unit 300.

With reference to FIGS. 5-11, 19 and 23-31, second drive converter assembly 250 of adapter assembly 200 includes second proximal drive shaft 214 rotatably supported within inner housing assembly 204. Second rotatable proximal drive shaft 214 includes a non-circular or shaped proximal end portion configured for connection with second connector or coupler 220 which is connected to respective second connector 120 of surgical device 100. Second rotatable proximal drive shaft 214 further includes a distal end portion 214 b having a threaded outer profile or surface.

Distal end portion 214 b of proximal drive shaft 214 is threadably engaged with an articulation bearing housing 252 a of an articulation bearing assembly 252. Articulation bearing assembly 252 includes a housing 252 a supporting an articulation bearing 253 having an inner race 253 b that is independently rotatable relative to an outer race 253 a. Articulation bearing housing 252 a has a non-circular outer profile, for example tear-dropped shaped, that is slidably and non-rotatably disposed within a complementary bore 204 c (FIGS. 25, 26, 29 and 33) of inner housing hub 204 a.

Second drive converter assembly 250 of adapter assembly 200 further includes an articulation bar 258 having a proximal portion 258 a secured to inner race 253 b of articulation bearing 253. A distal portion 258 b of articulation bar 258 includes a slot 258 c therein, which is configured to accept a portion 366, e.g., a flag, articulation link (FIG. 48) of loading unit 300. Articulation bar 258 functions as a force transmitting member to components of loading unit 300, as described in greater detail below.

With further regard to articulation bearing assembly 252, articulation bearing assembly 252 is both rotatable and longitudinally translatable. Additionally, it is envisioned that articulation bearing assembly 252 allows for free, unimpeded rotational movement of loading unit 300 when its jaw members 306, 308 are in an approximated position and/or when jaw members 306, 308 are articulated (FIG. 48).

In operation, as second proximal drive shaft 214 is rotated due to a rotation of second connector sleeve 220, as a result of the rotation of the second drive connector 120 of surgical device 100, articulation bearing assembly 252 is caused to be translated axially along threaded distal end portion 214 b of second proximal drive shaft 214, which in turn causes articulation bar 258 to be axially translated relative to outer tube 206. As articulation bar 258 is translated axially, articulation bar 258, being coupled to articulation link 366 of loading unit 300, causes concomitant axial translation of articulation link 366 of loading unit 300 to effectuate an articulation of tool assembly 304 (FIG. 48). Articulation bar 258 is secured to inner race 253 b of articulation bearing 253 and is thus free to rotate about the longitudinal axis X-X relative to outer race 253 a of articulation bearing 253.

As illustrated in FIGS. 6, 17, 18, 20-23, 25-28, 31 and 37-40 and as mentioned above, adapter assembly 200 includes a third force/rotation transmitting/converting assembly 260 supported in inner housing assembly 204. Third force/rotation transmitting/converting assembly 260 includes a rotation ring gear 266 fixedly supported in and connected to outer knob housing 202. Ring gear 266 defines an internal array of gear teeth 266 a (FIG. 6). Ring gear 266 includes a pair of diametrically opposed, radially extending protrusions 266 b (FIG. 6) projecting from an outer edge thereof. Protrusions 266 b are disposed within recesses defined in outer knob housing 202, such that rotation of ring gear 266 results in rotation of outer knob housing 202, and vice a versa.

Third force/rotation transmitting/converting assembly 260 further includes third rotatable proximal drive shaft 216 which, as described above, is rotatably supported within inner housing assembly 204. Third rotatable proximal drive shaft 216 includes a non-circular or shaped proximal end portion configured for connection with third connector 222 which is connected to respective third connector 122 of surgical device 100. Third rotatable proximal drive shaft 216 includes a spur gear 216 a keyed to a distal end thereof. A reversing spur gear 264 inter-engages spur gear 216 a of third rotatable proximal drive shaft 216 to gear teeth 266 a of ring gear 266.

In operation, as third rotatable proximal drive shaft 216 is rotated, due to a rotation of third connector sleeve 222, as a result of the rotation of the third drive connector 122 of surgical device 100, spur gear 216 a of third rotatable proximal drive shaft 216 engages reversing gear 264 causing reversing gear 264 to rotate. As reversing gear 264 rotates, ring gear 266 also rotates thereby causing outer knob housing 202 to rotate. As outer knob housing 202 is rotated, outer tube 206 is caused to be rotated about longitudinal axis “X” of adapter assembly 200. As outer tube 206 is rotated, loading unit 300, that is connected to a distal end portion of adapter assembly 200, is also caused to be rotated about a longitudinal axis of adapter assembly 200.

Adapter assembly 200 further includes, as seen in FIGS. 1B, 3-5, 16, 17, 20 and 24-26, an attachment/detachment button 272 supported thereon. Specifically, button 272 is supported on drive coupling assembly 210 of adapter assembly 200 and is biased by a biasing member 274 to an un-actuated condition. Button 272 includes lip or ledge 272 a formed therewith that is configured to snap behind a corresponding lip or ledge 108 b defined along recess 108 a of connecting portion 108 of surgical device 100. In use, when adapter assembly 200 is connected to surgical device 100, lip 272 a of button 272 is disposed behind lip 108 b of connecting portion 108 of surgical device 100 to secure and retain adapter assembly 200 and surgical device 100 with one another. In order to permit disconnection of adapter assembly 200 and surgical device 100 from one another, button 272 is depresses or actuated, against the bias of biasing member 274, to disengage lip 272 a of button 272 and lip 108 b of connecting portion 108 of surgical device 100.

With reference to FIGS. 1A, 2A, 2B, 3-5 and 24-26, adapter assembly 200 further includes a lock mechanism 280 for fixing the axial position and radial orientation of distal drive member 248. Lock mechanism 280 includes a button 282 slidably supported on outer knob housing 202. Lock button 282 is connected to an actuation bar 284 that extends longitudinally through outer tube 206. Actuation bar 284 moves upon a movement of lock button 282. Upon a predetermined amount of movement of lock button 282, a distal end of actuation bar 284 may move into contact with a lock out (not shown), which causes the lock out to cam a camming member 288 (FIG. 24) from a recess 249 in distal drive member 248. When camming member 288 is in engagement with recess 249 (e.g., at least partially within recess 249, see FIGS. 6 and 24), the engagement between camming member 288 and distal drive member 248 effectively locks the axial and rotational position of end effector 300 that is engaged with connection member 247.

In operation, in order to lock the position and/or orientation of distal drive member 248, a user moves lock button 282 from a distal position to a proximal position (FIGS. 25 and 26), thereby causing the lock out (not shown) to move proximally such that a distal face of the lock out moves out of contact with camming member 288, which causes camming member 288 to cam into recess 249 of distal drive member 248. In this manner, distal drive member 248 is prevented from distal and/or proximal movement. When lock button 282 is moved from the proximal position to the distal position, the distal end of actuation bar 284 moves distally into the lock out, against the bias of a biasing member (not shown), to force camming member 288 out of recess 249, thereby allowing unimpeded axial translation and radial movement of distal drive member 248.

Reference may be made to U.S. patent application Ser. No. 13/875,571, filed on May 2, 2013, the entire content of which is incorporated herein by reference, for a more detailed discussion of the construction and operation of lock mechanism 280.

With reference to FIGS. 1B, 6, 12A-15 and 25-28, adapter assembly 200 includes a proximal electrical assembly 290 supported on and in outer knob housing 202 and inner housing assembly 204. Proximal electrical assembly 290 includes an electrical connector 292 supported on a circuit board 294, for electrical connection to a corresponding electrical plug 190 disposed in connecting portion 108 of surgical device 100.

With particular reference to FIGS. 12A-12D, electrical connector 292 includes a plurality of electrical contact pins 293 and a housing or connector housing 295. Electrical contact pins 293 serve to allow for calibration and communication of life-cycle information to the circuit board of surgical device 100 via electrical plugs 190 that are electrically connected to the circuit board (not shown) of surgical device 100.

Each electrical contact pin 293 includes a distal portion 293 a and a proximal portion 293 b. Distal portion 293 a of each contact pin 293 is configured to engage circuit board 294, e.g., via soldering. Proximal portion 293 b of each contact pin 293 is configured to releasably engage corresponding electrical plug 190 disposed in connecting portion 108 of surgical device 100. With continued reference to FIGS. 12A-12D, distal portion 293 a of each electrical contact pin 293 is tapered to facilitate insertion into holes 294 a (FIG. 12B) of circuit board 294. Proximal portion 293 b of each electrical contact pin 293 includes a rectangular cross-section, and is tapered and chamfered to facilitate engagement and disengagement with electrical plug 190.

Additionally, each electrical contact pin 293 includes a hole 293 c extending laterally therethrough. Hole 293 c is configured to facilitate the connection between electrical contact pins 293 and housing 295. It is envisioned that housing 295 is over-molded, such that portions of the over-mold extend through holes 293 c in electrical contact pins 293. As can be appreciated, the engagement between electrical contact pins 293 and housing 295 helps maintain proper alignment of pins 293 to further facilitate engagement between electrical connector 292 and circuit board 294 and electrical plug 190, and to further facilitate engagement between electrical connector 292 and electrical plug 190. While seven electrical contact pins 293 are shown, it is envisioned that more or fewer electrical contact pins 293 are included with proximal electrical assembly 290.

With continued reference to FIGS. 12A-12D, housing 295 of electrical connector 292 includes a rectangular cross-section. The rectangular cross-section of housing 295 is configured to mate with a rectangular opening of proximal cap 210 a (FIGS. 5 and 6) of drive coupling assembly 210 to prevent radial movement therebetween.

Housing 295 also includes a plurality of projections 297 extending therefrom. Projections 297 each include a distal face 297 a and a proximal face 297 b. Distal face 297 a of each projection 297 is configured and positioned to contact circuit board 294 during insertion of electrical connector 292. Thus, distal face 297 a of each projection 297 prevents electrical contact pins 293 of electrical connector 292 from being inserted too far distally into holes 294 a of circuit board 294. While distal face 297 a of each projection 297 is illustrated as being flush with a distal face 295 a of housing 295 (FIG. 12D), it is envisioned that distal face 297 a of each projection 297 is positioned farther proximally or distally than distal face 295 a of housing 295. Proximal face 297 b of each projection 297 is configured and positioned to prevent disengagement between electrical connector 292 and circuit board 294, e.g., during disengagement between surgical device 100 and adapter assembly 200. More particularly, the proximal cap 210 of proximal electrical assembly 290 is configured to abut proximal face 297 b of at least one or all projections 297, thus preventing proximal movement of electrical connector 292 with respect to circuit board 294. In the illustrated embodiment, two projections 297 extend from a first surface 295 b of housing 295, and two projections 297 extend from a second surface 295 c of housing 295. However, housing 295 may include more or fewer projections 297.

Proximal electrical assembly 290 further includes a strain gauge 296 electrically connected to circuit board 294. Strain gauge 296 is provided with a notch 296 a which is configured and adapted to receive stem 204 d of hub 204 a of inner housing assembly 204. Stem 204 d of hub 204 a functions to restrict rotational movement of strain gauge 296. As illustrated in FIGS. 25-28, first rotatable proximal drive shaft 212 extends through strain gauge 296. Strain gauge 296 provides a closed-loop feedback to a firing/clamping load exhibited by first rotatable proximal drive shaft 212.

Proximal electrical assembly 290 also includes a slip ring 298 disposed within outer tube 206. Slip ring 298 is in electrical connection with circuit board 294 via a plurality of proximal wires 299. Slip ring 298 functions to permit rotation of first rotatable proximal drive shaft 212 and axial translation of drive coupling nut 244 while still maintaining electrical contact between electrical contact rings 298 a thereof and a distal electrical assembly 400 (see FIGS. 49-55) within adapter assembly 200, and while permitting the other electrical components to rotate about first rotatable proximal drive shaft 212 and drive coupling nut 244

Turning now to FIGS. 6, 11, 14, 32 and 33, inner housing assembly 204 has been designed to reduce incidents of racking of second proximal drive shaft 214 as drive shaft 214 rotates to axially translate articulation bearing assembly 252. Inner housing assembly 204 includes a hub 204 a having a distally oriented annular wall 204 b defining a substantially circular outer profile, and defining a substantially tear-drop shaped inner recess or bore 204 c. Bore 204 c of hub 204 a is shaped and dimensioned to slidably receive articulation bearing assembly 252 therewithin.

Inner housing assembly 204 includes a ring plate 254 a (FIG. 34) secured to a distal face of distally oriented annular wall 204 b of hub 204 a. Plate 254 a defines an aperture 254 e therethrough that is sized and formed therein so as to be aligned with second proximal drive shaft 214 and to rotatably receive a distal tip 214 c of second proximal drive shaft 214. In this manner, distal tip 214 c of second proximal drive shaft 214 is supported and prevented from moving radially away from a longitudinal rotational axis of second proximal drive shaft 214 as second proximal drive shaft 214 is rotated to axially translate articulation bearing assembly 252.

As illustrated in FIGS. 14, 32, 39 and 40, hub 204 a defines a feature (e.g., a stem or the like) 204 d projecting therefrom which functions to engage notch 296 a of strain gauge 296 of proximal electrical assembly 290 to measure forces experienced by shaft 212 as surgical device 100 is operated.

With reference to FIGS. 35-40, a plate bushing 230 of inner housing assembly 204 is shown and described. Plate bushing 230 extends across hub 204 a of inner housing assembly 204 and is secured to hub 204 a by fastening members. Plate bushing 230 defines three apertures 230 a, 230 b, 230 c that are aligned with and rotatably receive respective first, second and third proximal drive shafts 212, 214, 216 therein. Plate bushing 230 provides a surface against which first, second and third biasing members 224, 226 and 228 come into contact or rest against.

While plate bushing 230 has been shown and described as being a unitary monolithic piece, as illustrated in FIGS. 6 and 37-40, it is envisioned and within the scope of the present application that plate bushing 230 may be separated into several parts including, and not limited to, as seen in FIGS. 40-42, a support plate 230′ extending across drive shafts 212, 214, 216, and a separate bushing for each of drive shafts 212, 214, 216 and disposed between the support plate 230′ and hub 204 a of inner housing assembly 204. Support plate 230′ may include a pair of slots 230 a′, 230 b′ formed therein, which are configured and adapted to receive tabs 296 b of strain gauge 296 that project axially therefrom.

Turning now to FIGS. 43-47, an inner housing assembly 204′ according to another embodiment of the present disclosure is shown and will be described. In order to reduce incidents of racking (i.e., distal end 214 b of second proximal drive shaft 214 moving radially away from a longitudinal rotational axis thereof) of second proximal drive shaft 214 as drive shaft 214 rotates to axially translate articulation bearing assembly 252, inner housing assembly 204′ may include a reinforcement frame or bracket assembly 254′. Bracket assembly 254′ includes a first plate 254 a′ and a second plate 254 b′ integrally connected to and spaced a distance from first plate 254 a′ by a plurality of connecting rods 254 c′ extending therebetween.

First plate 254 a′ is disposed adjacent to or in close proximity to ring gear 266 and defines an aperture 254 d′ therethrough. Aperture 254 d′ is sized and formed in first plate 254 a′ so as to be aligned with second proximal drive shaft 214 and to permit second proximal drive shaft 214 to freely rotate therewithin. Second plate 254 b′ is spaced from first plate 254 a′ so as to be disposed at a distal free end of second proximal drive shaft 214. Second plate 254 b′ defines an aperture 254 e′ therethrough. Aperture 254 e′ is sized and formed in second plate or flange 254 b′ so as to be aligned with second proximal drive shaft 214 and to rotatably receive a distal tip 214 c of second proximal drive shaft 214.

In this manner, distal tip 214 c of second proximal drive shaft 214 is supported and prevented from moving radially away from a longitudinal rotational axis of second proximal drive shaft 214 as second proximal drive shaft 214 is rotated to axially translate articulation bearing assembly 252.

As illustrated in FIGS. 38, 46 and 47, inner housing assembly 204′ may include a reinforcing sleeve 255′ disposed about bracket assembly 254′ to further reinforce bracket assembly 254′. It is contemplated in an embodiment that reinforcing sleeve 255′ may be interposed between first plate 254 a′ and second plate 254 b′ of bracket assembly 254′. It is further contemplated that reinforcing sleeve 255′ may be interposed between second plate 254 b′ and a distally oriented face of proximal inner housing assembly 204′.

With particular reference to FIGS. 49-60B, further details and embodiments of proximal electrical assembly 290, distal electrical assembly 400, and the engagement therebetween are illustrated. Proximal electrical assembly 290 and distal electrical assembly 400 are configured to permit rotation of outer tube 206 of adapter assembly 200 with respect to handle housing 102 (FIG. 1A), while maintaining electrical contact between proximal electrical assembly 290 and distal electrical assembly 400.

With reference to FIGS. 52 and 53, distal electrical assembly 400 is shown and includes a contact housing or housing 410, a plurality of electrical contacts 420 extending from housing 410, and a plurality of wires 430 which electrically connect electrical contacts 420 with distal portions of force/rotation transmitting/converting assemblies 240, 250, 260. For example, a first electrical contact 422 is connected to first force/rotation transmitting/converting assembly 240 via a first wire 430 a, a second electrical contact 424 is connected to second force/rotation transmitting/converting assembly 250 via a second wire 430 b, and a third electrical contact 426 is connected to third force/rotation transmitting/converting assembly 250 via a third wire 430 c. Additionally, wires 430 include a first portion 432 which extends from a radially outer portion 412 of housing 410 in a curved manner and in a direction that is generally perpendicular to longitudinal axis “X.” A second portion 434 of each wire 430 is electrically coupled to first portion 432 of wires 430 and extends generally distally and longitudinally therefrom.

With particular reference to FIGS. 54 and 55, a radially inner portion 414 of housing 410 includes a pair of legs 416. Each leg 416 includes a curved portion 418 that is configured to mirror the curvature of slip ring 298. Additionally, each leg 416 includes a curved stepped portion 419. Housing 410 and slip ring 298 are dimensioned and configured such that slip ring 298 is positionable on a surface 419 a of stepped portions 419 and between sidewalls 419 b of stepped portions 419. This arrangement helps housing 410 maintain contact with slip ring 298 during rotation therebetween, for example.

With continued reference to FIGS. 54 and 55, a plurality of electrical contacts 420 is shown extending from housing 410. Each electrical contact 420 is configured to engage a single electrical contact ring 298 a of slip ring 298 (FIG. 54) to transmit electrical signals from that electrical contact ring 298 a to a respective wire 430 of distal electrical assembly 400. In the embodiment shown in FIGS. 54 and 55, for example, electrical contacts 420 extend in a cantilevered manner from housing 410 and are curved along a majority of their lengths. Further, the curvature of electrical contacts 420 is opposite from the curvature of slip ring 298 and is opposite from the curvature of curved portion 418 and stepped portion 419 of each leg 416 of housing 410. Additionally, each electrical contact 420 is configured to flex to help maintain contact with electrical contact rings 298 a of slip ring 298 upon rotation therebetween, for example. Further, the curvature of electrical contacts 420 enables uninterrupted contact between electrical contacts 420 and electrical contact rings 298 a upon rotation of housing 410 in either direction (i.e., clockwise and counter-clockwise) with respect to slip ring 298.

Referring now to FIGS. 56A-60B, other embodiments of electrical contacts 420 are shown. In FIGS. 56A-60B, portions of slip ring 298 and/or electrical contact rings 298 a are omitted and/or out of scale for clarity purposes. FIGS. 56A and 56B illustrate electrical contacts 420 a which include a leg 422 a and a foot 424 a. Each of leg 422 a and foot 424 a is generally linear. Foot 424 a extends from leg 422 a at an angle α_(a). It is envisioned that angle α_(a) is between about 100° and about 160°, or equal to about 135°. In this embodiment, an electrical connection is made at one location “EC1” where foot 424 a contacts electrical contact ring 298 a.

With reference to FIGS. 57A and 57B, another embodiment of an electrical contact 420 b is shown. Each electrical contact 420 b includes a pair of legs 422 b, and a foot 424 b extending from each leg 422 b such that each foot 424 b extends in an opposite direction from the other foot 424 b. It is also envisioned that each electrical contact 420 b includes a single leg 422 b with two feet 424 b extending therefrom in opposite directions. Each foot 424 b extends from its respective leg 422 b at an angle α_(b). It is envisioned that angle α_(b) is between about 100° and about 160°, or equal to about 135°. It is further envisioned that each foot 424 b extends from its respective leg 422 b at the same angle as the opposite foot 424 b or at a different angle from the opposite foot 424 b. In this embodiment, an electrical connection is made at two locations “EC1” and “EC2”—one where each foot 424 b contacts electrical contact ring 298 a. EC1 and EC2 provide redundant contacts to maintain electrical connections, for instance due to imperfection in surface 298 a.

With reference to FIGS. 58A and 58B, another embodiment of an electrical contact 420 c is shown. Electrical contact 420 c includes a leg 422 c, an ankle 423 c, and a foot 424 c. Ankle 423 c extends from leg 422 c at a first angle α_(c1), and foot 424 c extends from ankle 423 c at a second angle α_(c2). It is envisioned that first angle α_(c1) is between about 150° and about 175°, or equal to about 165°. And it is envisioned that second angle α_(c2) is between about 10° and about 60°, or equal to about 30°. Additionally, foot 424 c is curved along its length, e.g., its entire length. It is envisioned that the curvature of foot 424 c is equal to or greater than the curvature of electrical contact rings 298 a and/or slip ring 298. In this embodiment where the curvature of foot 424 c is greater than the curvature of electrical contact ring 298 a (FIG. 58a ), an electrical connection is made at two locations “EC1” and “EC2”—one where each foot 424 c contacts electrical contact ring 298 a. In this embodiment, the foot 424 c opens and conforms to ring 298 a maintaining multiple points of contact.

Referring to FIGS. 59A and 59B, another embodiment of an electrical contact 420 d is shown. Electrical contact 420 d includes a yoke 422 d including two legs 424 d, and a flexible contact 426 d spanning between legs 424 d. Each leg 424 d of yoke 422 d includes an opening 425 d configured to allow a portion of flexible contact 426 d to extend therethrough. Flexible contact 426 d includes an elongated portion 427 d with an enlarged portion 428 d at each end thereof. Elongated portion 427 d of flexible contact 426 d includes a smaller dimension than opening 425 d of leg 424 d, thus allowing elongated portion 427 d to extend through openings 425 d. Enlarged portions 428 d of flexible contact 426 d include a larger dimension than opening 425 d of leg 424 d, thus preventing enlarged portions 428 d from being able to extend through openings 425 d. Accordingly, flexible contact 426 d is maintained between legs 424 d of yoke 422 d. In this embodiment, an electrical connection is made at one location “EC1” where flexible contact 426 d contacts electrical contact ring 298 a. Additionally, it is envisioned that since flexible contact 426 d has the ability to flex with respect to yoke 422 d, electrical contact 420 d enables tolerances of electrical contact 420 d and/or slip ring 298 to be reduced.

With reference to FIGS. 60A and 60B, another embodiment of an electrical contact 420 e is shown. Electrical contact 420 e includes a leg 422 e and a ring 424 e extending therefrom. Ring 424 e is configured to wrap at least partially around electrical contact ring 298 a, and to have approximately the same radius of curvature of electrical contact ring 298 a along at least a portion of its length, thus maintaining an infinite amount of electrical connections therebetween. It is envisioned that ring 424 e and electrical contact ring 298 a contact each other for greater than 180°. It is further envisioned that ring 424 e forms between about 180° and about 360° of a circle. In embodiments where ring 424 e forms greater than about 180° of a circle, it is disclosed that ring 424 e is flexible enough to flex a sufficient amount during assembly to allow ring 424 e to be installed on electrical contact ring 298 a. That is, it is disclosed that a first end 425 e of ring 424 e and a second end 426 e of ring 424 e can be separated by a distance that is greater than the diameter of electrical contact ring 298 a.

Referring now to FIGS. 61-74, various embodiments of a guide 500 are shown. Generally, guide 500 is configured to help maintain engagement between housing 410 and slip ring 298 during assembly. In each of the embodiments, guide 500 includes a holder portion 510 and a spacer 550. Spacer 550 is immovably affixed to holder portion 510 and extends distally therefrom. Spacer 550 is configured to maintain slip ring 298 a predetermined distance proximally from slip ring cannula 700. Additionally, spacer 550 includes a plurality of arcuate, longitudinal passageways 552 which are configured to allow the plurality of wires 430 to pass therethrough.

With particular reference to FIGS. 61 and 62, a first embodiment of a guide is shown and is indicated as reference character 500. A holder portion 510 of guide 500 includes a rectangular aperture 512 extending therethrough. As shown in FIG. 62, rectangular aperture 512 is configured to allow a portion of housing 410 to extend therethrough. For instance, it is envisioned that legs 416 (obscured from view in FIG. 62) of housing 410 are insertable through rectangular aperture 512, and that a ledge 417 (see FIG. 54) of housing 410 abuts holder portion 510, thus preventing additional insertion of housing 410 through rectangular aperture 512. The perimeter of rectangular aperture 512 is slightly larger than the perimeter of the portion of housing 410 that extends therethrough, thus enabling a friction fit engagement therebetween.

Referring to FIGS. 63 and 64, another embodiment of a guide is shown and is referenced by character 500 a. A holder portion 510 a of guide 500 a includes a rectangular aperture 512 a extending therethrough. Additionally, holder portion 510 a of guide 500 a includes a flexible tee 520 a extending adjacent rectangular aperture 512 a and extending radially away from the longitudinal axis “X.” Flexible tee 520 a includes a shaft 522 a and crown 530 a. A first portion 524 a of shaft 522 a is flared and is in contact with remainder of holder portion 510 a, and a second portion 526 a of shaft 522 a engages crown 530 a.

As shown in FIG. 64, rectangular aperture 512 a is configured to allow a portion of housing 410 to extend therethrough. For instance, it is envisioned that legs 416 of housing 410 are insertable through rectangular aperture 512 a, and that ledge 417 (see FIG. 54) of housing 410 abuts holder portion 510 a, thus preventing additional insertion of housing 410 through rectangular aperture 512 a. To further maintain guide 500 a in contact with housing 410, shaft 522 a of flexible tee 520 a is configured to extend between a pair of projections 415 of housing 410, and crown 530 a is configured to abut a radially-outer surface 415 a of projections 415 (see FIG. 54). During installation between guide 500 a and housing 410, flexible tee 520 a is configured to flex away from housing 410 to allow housing 410 to be partially inserted into rectangular aperture 512 a of holder portion 510 a. Subsequently, flexible tee 520 a is configured to return to its non-flexed position to the location shown in FIG. 64.

With reference to FIGS. 65 and 66, another embodiment of a guide is shown and is referred to by reference character 500 b. A holder portion 510 b of guide 500 b includes a rectangular aperture 512 b extending therethrough. Additionally, holder portion 510 b of guide 500 b includes a post 520 b extending adjacent rectangular aperture 512 b and extending radially away from the longitudinal axis “X.” In disclosed embodiments, post 520 b includes a plurality of ribs 524 b extending along an inner surface 522 b of post 520 b and extending radially away from the longitudinal axis “X.”

As shown in FIG. 66, rectangular aperture 512 b is configured to allow a portion of housing 410 to extend therethrough. For instance, it is envisioned that legs 416 of housing 410 are insertable through rectangular aperture 512 c, and that ledge 417 (see FIG. 54) of housing 410 abuts holder portion 510 b, thus preventing additional insertion of housing 410 through rectangular aperture 512 b. To further maintain guide 500 b in contact with housing 410, post 520 b of holder portion 510 b is configured to extend between pair of projections 415 of housing 410 (see FIG. 54). Additionally, ribs 524 b on post 520 b are designed to be crushed during installation between guide 500 b and housing 410, thus providing an increased frictional engagement therebetween.

With reference to FIGS. 67-68, another embodiment of a guide is shown and is referred to by reference character 500 c. A holder portion 510 c of guide 500 c includes a rectangular aperture 512 c extending therethrough. Additionally, holder portion 510 c of guide 500 c includes a first post 520 c and a second post 530 c extending adjacent rectangular aperture 512 c and extending radially away from the longitudinal axis “X.” In disclosed embodiments, at least one of first post 520 c and second post 530 c includes a plurality of ribs 524 c, 534 c extending along an inner surface 522 c, 532 c of the respective first post 520 c and/or second post 530 c, and extending radially away from the longitudinal axis “X.”

As shown in FIG. 68, rectangular aperture 512 c is configured to allow a portion of housing 410 to extend therethrough. For instance, it is envisioned that legs 416 of housing 410 are insertable through rectangular aperture 512 c, and that ledge 417 (see FIG. 54) of housing 410 abuts holder portion 510 c, thus preventing additional insertion of housing 410 through rectangular aperture 512 c. To further maintain guide 500 c in contact with housing 410, first post 520 c of holder portion 510 c is configured to extend between the pair of projections 415 of housing 410 (see FIG. 54), and second post 530 c is configured to abut a rear wall 411 of housing 410 (see FIG. 55). Additionally, ribs 524 c, 534 c on first post 520 c and/or second post 530 c, respectively, are designed to be crushed during installation between guide 500 c and housing 410, thus providing an increased frictional engagement therebetween.

With reference to FIGS. 69 and 70, a second embodiment of housing 410 a is shown, which is configured to engage first embodiment of guide 500 (FIG. 70). As discussed above, holder portion 510 of guide 500 includes a rectangular aperture 512 extending therethrough. Rectangular aperture 512 is configured to allow a portion of housing 410 a to extend therethrough. For instance, it is envisioned that legs 416 a of housing 410 a are insertable through rectangular aperture 512, and that a ledge 417 a (see ledge 417 in FIG. 54) of housing 410 a abuts holder portion 510, thus preventing additional insertion of housing 410 a through rectangular aperture 512. The perimeter of rectangular aperture 512 is slightly larger than the perimeter of the portion of housing 410 a that extends therethrough, thus enabling a friction fit engagement therebetween. Additionally, housing 410 a includes a plurality of ribs 414 a extending along at least one lateral side 413 a of housing 410 a. Ribs 414 a are designed to fill any voids between lateral sides 413 a of housing 410 a and guide 500 to increase frictional engagement therebetween.

With reference to FIGS. 71-72, another embodiment of a guide is shown and is referred to by reference character 500 d. A holder portion 510 d of guide 500 d includes a rectangular aperture 512 d extending therethrough. Additionally, holder portion 510 d of guide 500 d includes a first flexible tab 520 d and a second flexible tab 530 d extending adjacent rectangular aperture 512 d and extending radially away from the longitudinal axis “X.” In the illustrated embodiment, each of first flexible tab 520 d and second flexible tab 530 d includes a one-way ratchet tooth 524 d, 534 d, respectively, thereon.

As shown in FIG. 72, rectangular aperture 512 d is configured to allow a portion of housing 410 to extend therethrough. For instance, it is envisioned that legs 416 of housing 410 are insertable through rectangular aperture 512 d, and that ledge 417 (see FIG. 54) of housing 410 abuts holder portion 510 d, thus preventing additional insertion of housing 410 through rectangular aperture 512 d. To further maintain guide 500 d in contact with housing 410, ratchet teeth 524 d, 534 d of first and second flexible tabs 520 d, 530 d, respectively, are configured to engage radially-outer surfaces 415 a of projections 415 (see FIGS. 54 and 72). During installation between guide 500 d and housing 410, flexible tabs 520 d and 530 d are configured to flex away from housing 410 in response to engagement between ratchet teeth 524 d, 534 d and ledge 417 to allow housing 410 to be partially inserted into rectangular aperture 512 d of holder portion 510 d. Subsequently, flexible tabs 520 d and 530 d are configured to return to their non-flexed position to the location shown in FIG. 72.

With reference to FIGS. 73-74, another embodiment of a guide is shown and is referred to by reference character 500 e. A holder portion 510 e of guide 500 e includes a rectangular aperture 512 e extending therethrough. Additionally, holder portion 510 e of guide 500 e includes a flexible tab 520 e extending adjacent rectangular aperture 512 e and extending radially away from the longitudinal axis “X.” In the illustrated embodiment, flexible tab 520 e includes a one-way ratchet tooth 524 e thereon.

As shown in FIG. 74, rectangular aperture 512 e is configured to allow a portion of housing 410 to extend therethrough. For instance, it is envisioned that legs 416 of housing 410 are insertable through rectangular aperture 512 e, and that ledge 417 (see FIG. 54) of housing 410 abuts holder portion 510 e, thus preventing additional insertion of housing 410 through rectangular aperture 512 e. To further maintain guide 500 e in contact with housing 410, ratchet tooth 524 e of flexible tab 520 e is configured to engage radially-outer surfaces 415 a of projections 415 (see FIGS. 54 and 74). During installation between guide 500 e and housing 410, flexible tab 520 e is configured to flex away from housing 410 in response to engagement between ratchet tooth 524 e and ledge 417 to allow housing 410 to be partially inserted into rectangular aperture 512 e of holder portion 510 e. Subsequently, flexible tab 520 e is configured to return to its non-flexed position to the location shown in FIG. 74.

Referring now to FIGS. 75-79, a spacer 600 and a slip ring contact holder 650 are shown in accordance with disclosed embodiments. Generally, spacer 600 and slip ring contact holder 650 are configured for mechanical engagement with one another and are configured to help maintain engagement between housing slip ring contact holder 650 and slip ring 298 during assembly. Further, in this embodiment, slip ring contact holder 650 combines some features of housings 410, 410 a and guides 500-500 e of previous embodiments. That is, in the embodiments disclosed in FIGS. 75-79, only one feature (i.e., slip ring contact holder 650) is necessary instead of two features (i.e., housing 410, 410 a and guides 500-500 e).

With reference to FIG. 75, spacer 600 is configured to maintain slip ring 298 a predetermined distance proximally from slip ring cannula 700. Additionally, spacer 600 includes an arcuate, longitudinal passageway 602, and a pair of slots 604. Passageway 602 is configured to allow the plurality of wires 430 (see FIG. 53) to pass therethrough, and each slot 604 is configured to mechanically engage one of two arms 660 of slip ring contact holder 650 for coupling spacer 600 and slip ring contact holder 650 (see FIGS. 76A and 76B).

Referring now to FIGS. 76A and 76B, slip ring contact holder 650 includes a body portion 670 and two arms 660 extending longitudinally therefrom. Body portion 670 is generally C-shaped and houses or is configured to house a plurality of contacts 680 a, 680 b, 680 c therein. Body portion 670 is configured to be positioned over slip ring 298 such that each contact 680 a, 680 b, 680 c engages a single contact ring 298 a of slip ring 298. Additionally, body portion 670 is rotatable about the longitudinal axis “X” with respect to slip ring 298, thus permitting rotation therebetween while maintaining electrical contact therebetween.

With continued reference to FIGS. 76A and 76B, slip ring contact holder 650 also includes apertures 672 a, 672 b, 672 c extending through body potion 670. Apertures 672 a, 672 b, 672 c are each configured to allow one extension portion 682 a, 682 b, 682 c (see FIG. 77) of contacts 680 a, 680 b, 680 c, respectively to pass therethrough. Each extension portion 682 a, 682 b, 682 c is configured to electrically connect to one of wires 430 a, 430 b, 430 c (see FIG. 53) to electrically connect contacts 680 a, 680 b, 680 c with distal portions of force/rotation transmitting/converting assemblies 240, 250, 260.

Additionally, slip ring contact holder 650 includes alignment tabs 690 a, 690 b, 690 c, 690 d configured to engage proximal and distal walls of slip ring 298, and help maintain contact with slip ring 298 during rotation of slip ring contact holder 650, for example.

With particular reference to FIGS. 77-79, spacer 600 and slip ring contact holder 650 are shown mechanically engaged. Here, each of the two arms 660 of slip ring contact holder 650 are mated with one slot 604 of spacer 600, thus mechanically coupling spacer 600 and slip ring contact holder 650. It is envisioned that a user can separate spacer 600 from slip ring contact holder 650 by forcing arms 660 toward body portion 670 and out of slots 604. Additionally, the embodiment of slip ring contact holder 650 illustrated in FIG. 79 includes a post 692 extending radially outwardly from body portion 670. It is envisioned that post 692 is configured to engage an inner wall of core tube 207 to help maintain proper radial and/or axial alignment therebetween, for example.

Referring now to FIGS. 15 and 80-85, various embodiments of a sleeve or slip ring cannula 700, 700 a, 700 b are shown. In general, slip ring cannula 700, 700 a, 700 b is included as a part of proximal electrical assembly 290 and is positioned on a portion of core tube 207 to protect and/or shield wires 299 extending between slip ring 298 and circuit board 294.

With particular reference to FIG. 15, slip ring cannula 700 includes a base portion 702, a longitudinal slit 710, a longitudinal wire track 720, a radially-extending post 730 adjacent a proximal portion of base portion 702, and a finger 740 extending proximally from a radially-outward portion of post 730. Referring now to FIG. 15 which illustrates slip ring cannula 700, and FIGS. 84-85 which show a different embodiment of a slip ring cannula 700 b, longitudinal slit 710 is formed in base portion 702 and is configured to facilitate assembly between slip ring cannula 700 and a core tube 207 (see FIGS. 82 and 83) of outer tube 206 (see FIG. 2A). Wire track 720 extends along base portion 702 radially opposite from longitudinal slit 710 and provides a path for wires 299 to extend within slip ring cannula 700 and between slip ring 298 and circuit board 294. Post 730 is configured to abut an inner wall of hub 204 a of inner housing assembly 204 to maintain the radial position of slip ring cannula 700 with respect to housing assembly 204. Finger 740 is configured such that when slip ring cannula 700 is engaged with housing assembly 204, hooks 742 of finger 740 hook around a proximal wall 205 of housing assembly 204 to maintain the longitudinal position of slip ring cannula 700 with respect to housing assembly 204 (see FIG. 85).

Turning now to FIGS. 80-83, another embodiment of a slip ring cannula 700 a is illustrated. Slip ring cannula 700 a includes a disc-like base portion 702 a, a slit 710 a extending radially outward from a central aperture 704 a, a wire track 720 a, and a pair of flexible tabs 730 a extending proximally from an outer periphery of base portion 702 a. Slip ring cannula 700 a is configured such that core tube 207 extends through central aperture 704 a. As shown with particular regard to FIGS. 81 and 83, wires 299 extend through wire track 720 a as wires 299 extend between slip ring 298 and circuit board 294 (see FIG. 12A, for example). Each flexible tab 730 a includes a one-way ratchet 732 a which is configured to engage a radial wall 204 e of hub 204 a (see FIG. 82). Engagement between flexible tabs 730 a and radial wall 204 e of hub 204 a provides linear stabilization of slip ring cannula 700 a with respect to housing assembly 204. Engagement between radially outward surfaces 734 a of flexible tabs 730 a and radial wall 204 e of hub 204 a provides radial stabilization of slip ring cannula 700 a with respect to housing assembly 204.

With reference to FIGS. 84 and 85, a third embodiment of slip ring cannula 700 b is shown. Slip ring cannula 700 b is similar to slip ring cannula 700, discussed above with reference to FIG. 15, but also includes a proximal passageway 744 b and a distal passageway 746 b extending through finger 740 b. Proximal and distal passageways 744 b, 746 b are configured to allow wires 299 and/or a cable to be threaded therethrough, as shown in FIGS. 84 and 85. It is envisioned that to facilitate assembling proximal electrical assembly 290 b around hub 204 a of housing assembly 204, an extra length 299 a of wires 299 would be helpful. This extra length 299 a of wires 299 would then be directed within adapter assembly 200 after circuit board 294 and strain gauge 296 (see FIG. 12A) have been assembled. As shown in FIG. 85, extra length 299 a of wires 299 are able to fit radially outward of proximal wall 205 of hub 204 a of housing assembly 204.

As can be appreciated, each embodiment of slip ring cannula 700, 700 a and 700 b, when assembled, will hold wires 299 taut in a linear manner with respect to slip ring 298, and will prevent articulation bearing assembly 252 (FIG. 25) from contacting wires 299. It is further envisioned that wires 299 are made from a material that is elastic and/or autoclavable. It is envisioned that these stretchable wires 299 are assembled over slip ring 298 in a first, non-stretched position. These wires 299 would then stretch toward a second position when slip ring 298 is assembled onto core tube 207. Here, wires 299 would be thin enough as to not interfere with articulation bearing assembly 252.

In operation, when a button of surgical device 100 is activated by the user, the software checks predefined conditions. If conditions are met, the software controls the motors and delivers mechanical drive to the attached surgical stapler, which can then open, close, rotate, articulate or fire depending on the function of the pressed button. The software also provides feedback to the user by turning colored lights on or off in a defined manner to indicate the status of surgical device 100, adapter assembly 200 and/or loading unit 300.

Reference may be made to U.S. Patent Publication No. 2009/0314821, filed on Aug. 31, 2009, entitled “TOOL ASSEMBLY FOR A SURGICAL STAPLING DEVICE” for a detailed discussion of the construction and operation of loading unit 300, as illustrated in FIGS. 1 and 48.

Any of the components described herein may be fabricated from either metals, plastics, resins, composites or the like taking into consideration strength, durability, wearability, weight, resistance to corrosion, ease of manufacturing, cost of manufacturing, and the like.

It will be understood that various modifications may be made to the embodiments of the presently disclosed adapter assemblies. Therefore, the above description should not be construed as limiting, but merely as exemplifications of embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure. 

What is claimed is:
 1. An adapter assembly for selectively interconnecting a surgical loading unit that is configured to perform a function and a surgical device that is configured to actuate the loading unit, the loading unit including an axially translatable drive member, and the surgical device including a rotatable drive shaft, the adapter assembly comprising: a housing configured and adapted for connection with the surgical device and to be in operative communication with each rotatable drive shaft of the surgical device; an outer tube having a proximal end supported by the housing and a distal end configured and adapted for connection with the loading unit, wherein the distal end of the outer tube is in operative communication with each of the at least one axially translatable drive member of the loading unit; at least one force/rotation transmitting/converting assembly for interconnecting a respective one drive shaft of the surgical device and a respective one axially translatable drive member of the loading unit; and an electrical assembly supported at least partially within at least one of the housing and the outer tube, the electrical assembly including: a proximal electrical assembly configured to electrically communicate with the surgical device, the proximal electrical assembly being rotatably fixed with respect to the surgical device, the proximal electrical assembly including a plurality of electrical contact rings disposed around a slip ring; and a distal electrical assembly disposed in electrical communication with the loading unit, the distal electrical assembly being rotatable with respect to the proximal electrical assembly, the distal electrical assembly including a plurality of electrical contacts disposed in mechanical cooperation with a contact housing, each electrical contact configured to contact and maintain an electrical connection with one of the plurality of electrical contact rings of the proximal electrical assembly during rotation of the distal electrical assembly with respect to the proximal electrical assembly.
 2. The adapter assembly according to claim 1, wherein each electrical contact of the distal electrical assembly is curved along at least a majority of its length.
 3. The adapter assembly according to claim 1, wherein each electrical contact of the distal electrical assembly includes a continuous curve in a first direction, and wherein the plurality of electrical contact rings of the proximal electrical assembly are curved in a second direction, the first and second directions being opposite from each other.
 4. The adapter assembly according to claim 1, wherein each electrical contact of the distal electrical assembly includes a leg and a foot, the leg extending from the contact housing, the foot extending at an angle from the leg, a portion of the foot configured to contact one of the plurality of electrical contact rings, wherein the angle is between about 100° and about 160°.
 5. The adapter assembly according to claim 1, wherein each electrical contact of the distal electrical assembly includes a leg and two feet, the leg extending from the contact housing, each foot extending at an angle from the leg in opposite directions, a portion of each foot configured to contact one of the plurality of electrical contact rings, wherein the angle is between about 100° and about 160°.
 6. The adapter assembly according to claim 1, wherein each electrical contact of the distal electrical assembly includes a leg, an ankle and an arcuate foot, the leg extending from the contact housing, the ankle extending at a first angle from the leg, and the arcuate foot extending at a second angle from the ankle, at least two portions of the arcuate foot are configured to contact one of the plurality of electrical contact rings, wherein the first angle is between about 150° and about 175°, and wherein the second angle is between about 10° and about 60°.
 7. The adapter assembly according to claim 6, wherein the arcuate foot includes a radius of curvature that is one of less than and equal to a radius of curvature of the plurality of electrical contact rings.
 8. The adapter assembly according to claim 1, wherein each electrical contact of the distal electrical assembly includes a leg, two feet extending from the leg in an opposite directions, and a flexible contact extending between the two feet, at least a portion of the flexible contact is configured to contact one of the plurality of electrical contact rings.
 9. The adapter assembly according to claim 8, wherein the flexible contact is movable with respect to at least one foot.
 10. The adapter assembly according to claim 1, wherein each electrical contact of the distal electrical assembly includes a leg and a ring, the leg extending from the contact housing, the ring extending from the leg, the ring configured to contact one of the plurality of electrical contact rings in an arc of greater than 180°.
 11. The adapter assembly according to claim 10, wherein the ring forms between about 180° and about 360° of a circle.
 12. The adapter assembly according to claim 1, wherein the contact housing includes a proximal leg configured to engage a proximal-most edge of the slip ring, and a distal leg configured to engage a distal-most edge of the slip ring.
 13. The adapter assembly according to claim 12, wherein each leg of the contact housing includes a stepped portion, at least part of the stepped portion configured to engage a radially-outermost portion of the slip ring.
 14. The adapter assembly according to claim 1, wherein the distal electrical assembly further includes a guide configured to help maintain a position of the contact housing with respect to the slip ring.
 15. The adapter assembly according to claim 14, wherein the guide is configured to help maintain a longitudinal position and a radial position of the contact housing with respect to the slip ring.
 16. The adapter assembly according to claim 14, wherein the guide includes an opening for receiving at least a portion of the contact housing therein, and wherein the guide includes a flexible member for extending between a pair of projections of the contact housing and for abutting a radially-outer surface of at least one of the projections of the contact housing.
 17. The adapter assembly according to claim 14, wherein the guide includes an opening for receiving at least a portion of the contact housing therein, and wherein the guide includes a first post extending adjacent a first portion of the opening for extending between a pair of projections of the contact housing.
 18. The adapter assembly according to claim 17, wherein the guide includes a second post extending adjacent a second portion of the opening for engaging a portion of the contact housing, the first portion and the second portion being on opposite sides of the opening.
 19. The adapter assembly according to claim 14, wherein the guide includes an opening for receiving at least a portion of the contact housing therein, wherein the contact housing includes at least one projection, and wherein the guide includes at least one flexible tab for engaging a radially-outer surface of the at least one projection of the contact housing.
 20. The adapter assembly according to claim 14, wherein the guide includes an opening for receiving at least a portion of the contact housing therein, wherein the contact housing includes at least two projections, and wherein the guide includes at least two flexible tabs, each flexible tab configured for engaging a radially-outer surface of one of the at least two projections of the contact housing. 